Adjustable cover assembly for cut-off tool

ABSTRACT

A cover assembly for use on a cut-off tool. The tool has a housing, a motor having a rotor, and an output shaft for fastening a cutting wheel. The shaft is connected to the rotor, so the output shaft turns about an axis aligned with the centerline of the rotor. The assembly includes a cover sized for receiving the cutting wheel. The cover has a collar sized for receiving a portion of the tool surrounding the output shaft. The collar is fastenable to the tool. The tool includes a foot having an elongated planar sole pivotally attached to the cover. The foot is pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole. The cover includes a clamp for clamping the foot to the cover when the distance the cutting wheel extends from the sole corresponds to a desired maximum cutting depth.

BACKGROUND

The present disclosure generally relates to cut-off tools, and more particularly, to an accessory cover assembly for a cut-off tool providing a selectively adjustable depth stop, perpendicular cutting guide, and stabilization support.

Cut-off tools are hand-held power tools suitable for cutting light materials such as sheet metal and thin plate. Typically, these tools have a grip sized for a user to hold in one hand when operating the tool. Cut-off tools rotate a cutting wheel about an axis generally aligned with a centerline of a motor housed in the grip. The size and shape of the tool, as well as, the orientation of the cutting wheel facilitate using the tool in tight work spaces that would be difficult to reach with many most two-handed tools. In addition, cut-off tools are well-suited for cutting protruding material flush with the surface from which it protrudes. Cut-off tools may have a fully exposed cutting wheel to improve the visibility of the wheel. Although visibility of a cutting wheel improves cutting precision, an exposed wheel tends to propel debris and sparks from the surface being cut. The debris and sparks may damage surfaces they contact. Accessory cutting wheel covers are sometimes used to enclose a portion of the wheel to block debris and sparks from being thrown beyond the cover. Frequently, the covers enclose about half of the circumference of the wheel to limit the directions in which the debris and sparks travel. One downside of using a cover is that the cover may obscure the cutting wheel and the surface of the material being cut. The lack of visibility can result in cutting too deep, potentially damaging objects below the material, or cutting oblique to the surface of the material, potentially resulting in rework or repair. Thus, a need exists for a cover that limits cutting depth and facilitates making cuts normal or perpendicular to the surface being cut. Moreover, using cut-off tools requires a steady hand to make a straight cut. Therefore, a need also exists for providing the tool with a stabilizing support to facilitate making good cuts.

SUMMARY

In one aspect, the present disclosure includes a cover assembly for use on a cut-off tool. The tool has a housing and a motor having a rotor mounted inside the housing. The motor is selectively operable to rotate the rotor about a centerline. Further, the cut-off tool has an output shaft adapted for fastening a cutting wheel to the shaft. The output shaft is operatively connected to the rotor, so the output shaft turns about an axis that is generally aligned with the centerline of the rotor. The cover assembly comprises a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft. The cover has a collar sized for receiving a portion of the tool surrounding the output shaft. The collar is releasably fastenable to the portion of the tool to attach the cover to the tool. The tool also includes a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the tool. The foot is selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole. The cover includes a clamp positioned for clamping the foot to the cover when the distance the cutting wheel extends from the sole corresponds to a desired maximum cutting depth.

In another aspect, the disclosure includes a cut-off tool, comprising a housing and a motor having a rotor mounted inside the housing. The motor is selectively operable to rotate the rotor about a centerline. The tool includes an output shaft adapted for fastening a cutting wheel to the shaft. The output shaft is operatively connected to the rotor, so the output shaft turns about an axis when the motor operates. In addition, the tool comprises a cover assembly, including a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft. The cover has a collar sized for receiving a portion of the housing surrounding the output shaft. The collar is releasably fastenable to the portion of the housing to attach the cover to the housing. Further, the cover assembly includes a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the housing. The foot is selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole.

Other aspects of the disclosure will be apparent in view of the following description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of a cut-off tool having an accessory cover assembly attached over a cutting wheel;

FIG. 2 is a fragmentary side elevation of the cut-off tool having the cutting wheel articulated upward;

FIG. 3 is a fragmentary side elevation of the cut-off tool having the cutting wheel articulated downward;

FIG. 4 is a front elevation of the cut-off tool and the accessory cover assembly shown set to a first maximum cut depth;

FIG. 5 is a front elevation of the cut-off tool and the accessory cover assembly shown set to a second maximum cut depth;

FIG. 6 is a front elevation of an accessory cover assembly removed from the cut-off tool;

FIG. 7 is a rear elevation of the accessory cover assembly removed from the cut-off tool;

FIG. 8 is a fragmentary top plan of the accessory cover assembly connected to the cut-off tool; and

FIG. 9 is a bottom plan of the accessory cover assembly removed from the cut-off tool;

Corresponding reference characters indicate corresponding parts throughout the drawings.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to FIG. 1, a cut-off tool is designated in its entirety by the reference number 20. The cut-off tool 20 comprises a housing 22 having a grip 24 sized and shaped for enabling a user to hold the tool 20 in one hand. A motor 26 mounted in the housing 22 includes a rotor 28 that rotates about a centerline 30 when the motor is energized. Although the motor may be electric, the illustrated motor 26 is a conventional pneumatic motor powered by pressurized shop air entering the housing 22 through a hose (not shown) attached to a fitting 32 at a rearward end of the housing. A lever 34 is pivotally attached to the housing 22 adjacent the grip 24. The lever 34 is positioned so a user holding the tool 20 by the grip 24 can pivot the lever toward the grip using the fingers of the grasping hand to open a valve 36 and allow pressurized air to the enter the motor 26 and turn the rotor 28 about its centerline 30. The rotor 28 is operatively connected to an output shaft 38 by a power shaft 40 extending through a flexible coupling or joint 42 allowing the output shaft to angle upward or downward as shown in FIGS. 2 and 3, respectively.

Although the output shaft 38 pivots upward or downward, the shaft rotates about an axis 44 generally aligned with the centerline 30 of the rotor 28. A lock sleeve 46 is provided to maintain the output shaft 38 in a selected orientation. To articulate or flex the joint 42 the user moves the lock sleeve 46 forward against a biasing force of a retainer spring (not shown), disengaging a locking mechanism so the joint is free to articulate up or down to a desired orientation. The lock sleeve 46 is biased rearward toward its locked position by the retainer spring. Once the output shaft 38 is in the selected orientation, the user releases the lock sleeve 46, allowing it to move rearward to engage the locking mechanism and hold the joint 42 and output shaft in their selected orientations. The power shaft 40 transmits torque between the rotor 28 and the output shaft 38 regardless of the orientation of the joint 42 relative to the housing 22. Bushings and bearings (not shown) are provided inside the joint 42 to allow the output shaft 38 and power shaft 40 to spin freely inside the joint while the joint remains stationary in its selected orientation. A cutting wheel 48 is fastened to the output shaft 38 by a bolt 50 and a pair of washers 52 so the cutting wheel rotates about the output shaft axis 44. The tool 20 may have a lever stop 54 to prevent the lever 34 from inadvertently actuating the valve 36. Further, the tool 20 may include a regulator knob (not shown) for controlling a speed at which the rotor 28 turns about the centerline 30 and the output shaft 38 turns about its axis 44. The tool 20 may also include other features such as a reverse selector (not shown) for selectively reversing a direction in which the rotor 28 and the output shaft 38 rotate inside the housing 22. As these features and the operation of the tool 20 described above are conventional and well understood by those skilled in the art, they will not be described in further detail.

As illustrated in FIGS. 1-3, an adjustable cover assembly, generally designated by 60, is removably fastened to the joint 42 adjacent the output shaft 38. The assembly 60 comprises a cover, generally designated by 62, and a foot, generally designated by 64, pivotally mounted on the cover for selectively positioning the cover 62 relative to the foot 64 in different positions such as shown in FIGS. 4 and 5. FIGS. 6-8 show that the cover 62 includes a semi-annular body, generally designated by 66. The body 66 encloses an upper half of the cutting wheel 48 to prevent contact with a corresponding edge, front face, and back face of the cutting wheel. Further, the body 66 includes has a semi-cylindrical outer surface 68, a planar front face 70 extending radially inward from a forward end of the outer surface, and a planar rear face 72 extending radially inward from a rearward end of the outer surface. As will be appreciated by those skilled in the art, the cover 62 limits the directions in which debris and sparks travel away from the wheel 48. As further shown in FIGS. 4-6, a generally semicircular opening 76 is provided in the front face 70 of the cover 62 adjacent to the bolt 50 attaching the cutting wheel 48 to the output shaft 38 (FIG. 1). This opening 76 provides access for inserting and tightening the bolt 50 with a wrench when installing the cutting wheel 48 or for loosening and removing the bolt when removing the cutting wheel 48.

FIGS. 6-8 illustrate a cylindrical collar 78 extending rearward from the rear face 72 of the cover 62 in line with the axis 44 and opposite the semicircular opening 76. As shown in FIGS. 7 and 8, the collar 78 includes a pair of ears 80 a, 80 b extend outward from the collar and separated by a gap 82 extending longitudinally from a rearward end of the collar to a position near the rear face 72 of the cover 62. A machine screw 84 extends through an opening in flange 80 a to a threaded hole 86 in the opposing flange 80 b. A washer 88 may be provided between the head of the machine screw 84 and the flange 80 a. Tightening the screw 84 draws the flanges 80 a, 80 b toward each other and closes the gap 82 to clamp the collar 78 of the cover 62 to outer surface of the joint 42 as shown in FIG. 8. Although the cover may be made from other materials without departing from the scope of this description, the illustrated cover 62 is machined from cast aluminum. Visible exterior surfaces of the cover 62 may be finished by grit blasting to improve appearance of the cover.

FIGS. 6-9 illustrate that the foot 64 includes a generally rectangular sole 90 having opposite curved tabs 92 extending upward from one end. The tabs 92 are fastened to the front and rear faces 70, 72 of the cover 62 with screw fasteners 94. The tab 92 and screw fastener 94 arrangement permits the sole 90 to pivot away from and toward the cover 62 as shown in FIGS. 4 and 5, respectively. As further shown in FIG. 9, a broad slot 96 is provided along the sole 90 to allow the cutting wheel 48 to pass through the sole 90. As shown in FIG. 1, the sole 90 is oriented at a parallel to the axis 44 of the cutting wheel or perpendicular to a plane of the cutting wheel 48. Thus, the sole 90 may be used as a guide to ensure the cutting wheel 48 cuts the material perpendicular to its surface. As will be appreciated by those skilled in the art, the user may rest the sole 90 on the material being cut to support the tool 20 and ensure stability. A cut can then be made by rotating the tool 20 to contact the cutting wheel 48 with the material.

As illustrated in FIG. 7, a long arcuate tongue 98 extends upward from an end of the sole 90 opposite the tabs 92. The tongue 98 is positioned adjacent the rear face 72 of the cover 62. A curved slot 100 extends along the tongue 98. The curved slot 100 follows a circular path that sweeps through an arc centered on the screw fasteners 94. A winged screw fastener 102 extends through the curved slot 100 to a threaded hole (not shown) in the rear face 72 of the cover 62. When the foot 64 and cover 62 are pivoted to a desired angle, the winged screw fastener 102 is selectively tightened to maintain the desired angle. The winged screw fastener 102 clamps the tongue 98 to the cover 62 to maintain the position of the foot 65 relative to the cover. When a different angle is desired, the screw 102 may be loosened to allow the foot 64 to pivot relative to the cover 62. As will be apparent to those skilled in the art, when the angle between the foot 64 and cover 62 changes, a distance D that the cutting wheel 48 extends below the sole 90 changes as shown by comparing FIGS. 4 and 5. Thus, the sole 90 forms a stop that sets a maximum depth of cut that the cutting wheel 48 can make. The stop ensures the cutting wheel 48 does not extend below the material M by more than a desired distance.

Shaped gussets 104 extend between the tongue 98 and the sole 90 and the tab 92 positioned on the same side of the sole as the tongue. The gussets 104 stiffen the sole 90 to prevent bending and strengthen the connections between the sole and the tongue 98 and between the sole and tab 92. The gusset 104 and sole 90 include a shaped notch 106 to provide clearance for the joint 42 when the cover 62 and foot 64 are brought close to one other. Although the foot may be made from other materials without departing from the scope of this description, the illustrated foot 64 is machined from cast aluminum. Visible surfaces of the foot 64 may be grit blasted to improve the appearance of the foot.

To install the accessory adjustable cover assembly 60, the cutting wheel 48 is removed from the tool 20. The machine screw 84 extending through the ears 80 a, 80 b of the collar 78 is loosened to open the gap 82 and enable the collar to slide over the joint 42. Once the collar 78 is in position on the joint 42, the machine screw 84 is tightened to hold the cover assembly 60 on the tool 20. Should the user desire to change the orientation of the cover assembly 60 relative to the throttle lever 34 and grip 24, the machine screw 84 is loosened, allowing the collar 78 to rotate relative to the joint 42 before retightening the machine screw. Once the cover assembly 60 is attached to the tool, the cutting wheel 48 may be installed by first positioning a washer 52 on the output shaft 38, followed by the cutting wheel and a second washer, before fastening the bolt 50 to the output shaft to hold the cutting wheel in place. The cutting wheel 48 may be centered in the broad slot 96 in the sole 90 by loosening the machine screw 84 and repositioning the assembly 60 before retightening the machine screw to hold the cover assembly in position. With the cover assembly 60 position adjusted as described above, the wing bolt 102 may be loosened to adjust the distance D the cutting wheel 48 protrudes below the sole 90. When the cover 62 and foot 64 are oriented to provide the desired distance D, the wing bolt 102 is retightened to provide a stop to ensure the maximum cutting depth setting. As will be apparent to those skilled in the art, the illustrated articulating cut-off tool 20 is well suited for use with the cover assembly 60 because the joint 42 can be angled to provide optimal clearances and angles for the tool 20.

When the cutting wheel 48 is rotating in its typical forward direction, the debris and sparks travel away from the cutting wheel toward the pivot axis defined by the screws 94 holding the tabs 92 to the cover 62. Because the distance between the sole 90 and cover 62 remains constant at the end of the sole having the tabs 92, the cover consistently contains the debris and sparks when the cutting wheel 48 rotates clockwise as shown in FIGS. 4 and 5 regardless of the angle between the cover and sole.

Having described the drawings in detail, it will be apparent that modifications and variations may be made without departing from the scope of the subject matter defined in the appended claims.

As various changes could be, made in the above constructions, products, and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

When introducing elements, the articles “a”, “an”, “the”, and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including”, and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 

What is claimed is:
 1. A cover assembly for use on a cut-off tool having a housing, a motor having a rotor mounted inside the housing, said motor being selectively operable to rotate the rotor about a centerline, the cut-off tool having an output shaft adapted for fastening a cutting wheel thereto, said output shaft being operatively connected to the rotor so the output shaft turns about an axis that is generally aligned with the centerline of the rotor, said cover assembly comprising: a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft, said cover having a collar sized for receiving a portion of the tool surrounding the output shaft, the collar being releasably fastenable to said portion of the tool to attach the cover to the tool; and a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the tool, the foot being selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole; wherein the cover includes a clamp positioned for clamping the foot to the cover when the distance the cutting wheel extends from the sole corresponds to a desired maximum cutting depth.
 2. A cover assembly as set forth in claim 1, wherein the foot includes an arcuate tongue extending from the sole and adjacent the cover, and the clamp comprises a screw positioned for fastening the tongue to the cover.
 3. A cover assembly as set forth in claim 2, wherein: the arcuate tongue has a curved slot sized for receiving the screw, said slot follows a circular path that sweeps through an arc centered on an imaginary line through the cover about which the sole pivots; and the screw extends through the slot and is threaded into the cover.
 4. A cover assembly as set forth in claim 1, wherein the sole extends perpendicular to the cutting wheel when the collar is fastened to the portion of the tool and the cutting wheel is fastened to the output shaft.
 5. A cover assembly as set forth in claim 1, wherein the sole has a slot sized and shaped for receiving the cutting wheel and allow the cutting wheel to extend through sole.
 6. A cover assembly as set forth in claim 1, wherein the cover includes a semi-cylindrical outer surface, a planar front face extending radially inward from a forward end of the outer surface, and a planar rear face extending radially inward from a rearward end of the outer surface, so the cover encloses a portion of the cutting wheel.
 7. A cover assembly as set forth in claim 6, wherein the front face of the cover has an opening sized for providing clearance to install and remove the cutting wheel from the output shaft when the collar is fastened to the portion of the tool.
 8. A cover assembly as set forth in claim 7, wherein: the collar extends rearward from the rear face of the cover and includes a pair of ears separated by a longitudinal gap; and the collar tightens around the portion of the tool when the pair of ears are moved closer together to reduce a width of the gap.
 9. A cover assembly as set forth in claim 8, wherein the collar includes a screw extending between the pair of ears to pull the pair of ears closer together.
 10. A cover assembly as set forth in claim 1, in combination with the cut-off tool.
 11. A cut-off tool, comprising: a housing; a motor having a rotor mounted inside the housing, the motor being selectively operable to rotate the rotor about a centerline; an output shaft adapted for fastening a cutting wheel thereto, said output shaft being operatively connected to the rotor so the output shaft turns about an axis when the motor operates; and a cover assembly, including: a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft, said cover having a collar sized for receiving a portion of the housing surrounding the output shaft, the collar being releasably fastenable to said portion of the housing to attach the cover to the housing; and a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the housing, the foot being selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole.
 12. A cut-off tool as set forth in claim 11, wherein the cover includes a clamp positioned for clamping the foot to the cover when the distance the cutting wheel extends from the sole corresponds to a desired maximum cutting depth.
 13. A cut-off tool as set forth in claim 12, wherein the foot includes an arcuate tongue extending from the sole and adjacent the cover, and the clamp comprises a screw positioned for fastening the tongue to the cover.
 14. A cut-off tool as set forth in claim 13, wherein: the arcuate tongue has a curved slot sized for receiving the screw, said slot follows a circular path that sweeps through an arc centered on an imaginary line through the cover about which the sole pivots; and the screw extends through the slot and is threaded into the cover.
 15. A cut-off tool as set forth in claim 11, wherein the sole extends perpendicular to the cutting wheel when the collar is fastened to the portion of the housing and the cutting wheel is fastened to the output shaft.
 16. A cut-off tool as set forth in claim 11, wherein the sole has a slot sized and shaped for receiving the cutting wheel and allow the cutting wheel to extend through sole.
 17. A cut-off tool as set forth in claim 11, wherein the cover includes a semi-cylindrical outer surface, a planar front face extending radially inward from a forward end of the outer surface, and a planar rear face extending radially inward from a rearward end of the outer surface, so the cover encloses a portion of the cutting wheel.
 18. A cut-off tool as set forth in claim 17, wherein: the collar extends rearward from the rear face of the cover and includes a pair of ears separated by a longitudinal gap; and the collar tightens around the portion of the housing when the pair of ears are moved closer together to reduce a width of the gap.
 19. A cut-off tool as set forth in claim 18, wherein the collar includes a screw extending between the pair of ears to pull the pair of ears closer together.
 20. A cut-off tool as set forth in claim 11, wherein: the housing includes a joint to selectively articulate the tool; and the collar releasably fastens to joint to attach the cover to the housing. 